The present invention is a diaper or incontinent brief which offers increased comfort for the wearer and which is highly resistant to leakage during use. One version of the pad has attachment straps which are releasable without tearing the moisture impervious backing film and which may later be reattached if desired.
Disposable diapers and similar products have gained wide acceptance in recent years. While these products are used mainly for infants prior to toilet training, they are also used for older children and adults with problems of bladder or bowel incontinence. Until very recently, most such adult products have completely encircled the hip region of the wearer so that they resemble a very bulky panty when in use. In the adult sizes in particular, this wrap-around construction results in large areas of skin being tightly covered in a moisture impervious garment. In hot weather, such a garment becomes very uncomfortable for the wearer. Recently, products have appeared on the market which are open at the sides and have somewhat the appearance of a loin cloth when worn. These products are finding excellent marketplace acceptance by the users since they are much cooler and generally more comfortable than the bulky products which have full hip enclosure. Additionally, these newer products are more economical to manufacture and more efficient in use because they do not place large volumes of the absorbent pad in areas so remote from the point of wetting that it is inefficiently utilized. One such product is disclosed in an earlier patent application of the present inventor, Ser. No. 06/476,675, filed Mar. 18, 1983. This attachment uses straps which are adhesively held in place but which may be later removed and then reapplied without damaging the thin plastic coversheet common to nearly all garments of this type. Another product of this type has recently appeared in the marketplace and is sold as Depend undergarments by the Kimberly-Clark Corporation, Neenah, Wis. Depend is a registered trademark of the manufacturer. This product uses button-on elastic straps to hold it in place on the wearer.
One problem which has received a great deal of attention is prevention of leakage in the thigh and waist areas of disposable diapers. Originally, this problem was attacked by the use of the so-called Z-fold configuration in which a folded portion near the edge of the diaper served somewhat as a seal to prevent leakage in the thigh area. However, the Z-fold configuration was only moderately successful in preventing leakage and had the additional disadvantage of placing a great deal of uncomfortable bulk in the crotch area of the wearer. Later inventors have tackled this problem with some success. U.S. Pat. No. 3,860,003 to Buell is one example. In this inventor's preferred construction, the pad and its enclosing envelope are trimmed in a generally hourglass-type configuration to reduce the bulk in the crotch area. Additionally, elastic strips are located along the margins in the crotch area so that in use these form seals against leakage as they are stretched around the thighs of the wearer. A modification of this construction is seen in U.S. Pat. No. 4,050,462 to Woon et al. In U.S. Pat. No. 4,253,461, Strickland et al. have also retained the narrowed crotch with elastic along the margins of the crotch area. In addition, they have provided an extra pair of attachment tapes to guarantee a tighter fit in the waist area.
The use of elastic margins on disposable diapers goes back well before the time of the above inventions. U.S. Pat. No. 2,273,542 to Tasker shows a rectangular diaper having full-length elastic inserts along each longitudinal margin. Tasker takes advantage of the additional bulk in the crotch area to form a pocket which is said to act as a waste receptacle.
In conventional diapers, an absorbent pad, usually of fluffed wood pulp enclosed within thin tissue layers, is retained within an envelope comprising a thin thermoplastic backsheet and a moisture impervious topsheet of non-woven material which is worn adjacent to the skin of the wearer. This envelope, as well as its included absorbent pad, has been assembled in many different configurations. The products currently finding considerable acceptance as infant diapers usually contain an hourglass-shaped pad within a similarly configured envelope of somewhat larger dimensions. Examples having this construction are seen in each of the aforementioned patents to Buell, Woon et al., and Strickland et al. However, it is known to put a generally hourglass configured pad within a rectangular envelope, as is seen in FIG. 6 of the Buell patent.
In pads having cutout portions to give them an hourglass-shaped configuration, it is normal for the longitudinal center of the cutout to be located on the transverse centerline of the diaper to create an essentially symmetrical configuration. The cutouts themselves do not necessarily show the front-to-back symmetry on either side of their centerline. Rather surprisingly, all of the asymmetrical cutout portions of which the present inventor is aware seem to widen out faster in the front portion of the diaper than they do in the back portion. A rather striking example of this is seen in U.S. Pat. No. 3,794,033 to Ryan.
Most of the significant design improvements to date in disposable diapers have been made in those intended for use on infants, since this represents the largest portion of the market for the product. When attention began to be directed toward disposable diapers or briefs for incontinent adults, the earlier products were simply scaled-up versions of those intended for infant use. These early products were not very satisfactory due to the obvious anatomical differences between infants and adults. They were hot, bulky, and uncomfortable for the wearer and leakage was an ever-present problem. Another problem was caused by the use of adhesive-coated attachment tapes. While these represent a distinct convenience in comparison to safety pins, in the past they could not be removed without tearing the thermoplastic backing sheet on the front of the diaper.
The present invention addresses all of the above problems and provides technically acceptable solutions which add little or nothing to the manufacturing cost of the articles.